Question

Exposed to sufficiently high magnetic fields, materials saturate, or approach a maximum magnetization. Would you expect the saturation (maximum) magnetization of paramagnetic materials to be much less than, roughly the same as, or much greater than that of ferromagnetic materials? Explain why.

Short answer

Answer: The saturation magnetization of paramagnetic materials is much less than that of ferromagnetic materials. This is due to the weak magnetic moments and random orientation of paramagnetic materials in the absence of an external magnetic field, resulting in a meager response to the applied field. In contrast, ferromagnetic materials have strong magnetic moments that spontaneously align, producing strong magnetization when exposed to an external magnetic field.

Step-by-step solution

Understand Paramagnetic Materials

Paramagnetic materials are materials in which the individual atoms or ions have a net magnetic moment due to unpaired electrons in their atomic or molecular orbitals. In the absence of an external magnetic field, these materials have a random orientation of their magnetic moments, resulting in no net magnetization. When an external magnetic field is applied, the material gets magnetized due to the alignment of these magnetic moments, increasing the material's magnetization.

Understand Ferromagnetic Materials

Ferromagnetic materials are the materials in which their atoms' net magnetic moments spontaneously align themselves in a parallel manner, even in the absence of an external magnetic field. This alignment between the neighboring moments results in the creation of different magnetic domains in the material. When an external magnetic field is applied to a ferromagnetic material, these domains grow and align in the direction of the applied field, significantly increasing the material's magnetization.

Compare Saturation Magnetization

Now that we understand the characteristics of paramagnetic and ferromagnetic materials, we can compare their saturation magnetization. Saturation magnetization is achieved when all possible magnetic moments in a material are aligned in the field direction. For paramagnetic materials, due to their weak magnetic moments and random orientation in the absence of a magnetic field, their response to an external magnetic field is minuscule. Hence, the saturation magnetization of paramagnetic materials will be much less. On the other hand, ferromagnetic materials possess strong magnetic moments that spontaneously align, creating magnetic domains. When exposed to an external magnetic field, they exhibit a highly responsive behavior, resulting in a large increase in magnetization. Consequently, the saturation magnetization of ferromagnetic materials will be significantly higher.

Conclusion

In conclusion, the saturation (maximum) magnetization of paramagnetic materials is expected to be much less than that of ferromagnetic materials. This is because paramagnetic materials possess weak magnetic moments and random orientation in the absence of an external magnetic field, resulting in a meager response to the applied field. In contrast, ferromagnetic materials have strong magnetic moments that spontaneously align, producing strong magnetization when exposed to an external magnetic field.